Analysis and prevention of spontaneous combustion of Angren coal

The article addresses the studies and prevention of spontaneous combustion of Angren lignite. The theory of spontaneous combustion of coal as a chemical process in coal mining is given in brief, and the spontaneous combustion conditions are listed. It is emphasized that chemical activity of coal grows under low temperatures which contribute to spontaneous combustion, and is sensitive to hot regional climate, which is studied therefore. High temperature (from +25 to +50 0С) induces a jump in the chemical activity of Angren coal. The main characteristic of coal seam properties is defined together with the permeability of coal, which is the coal seam capacity to transmit liquid under the action of the applied pressure gradient. It is found that loose coal accumulation and mixture with dirt rock on benches, in re-handling in mined-out void of an open pit, in external and internal dumps and in coal storages is the major source of spontaneous combustion of lignite. The implemented research shows that preliminary humidification of coal seams lowers chemical activity of Angren lignite by 60%, which is an efficient tool of spontaneous combustion prevention, weakens coal strength and effectively suppresses dusting in opencast air. At the present time, output of coal mining industry fails to satisfy the needs of the Republic of Uzbekistan. In this connection, Uzbekistan President’s resolution PP-3054 dated June 13, 2017, on «…the coal industry advance and modernization program», providing an increase in coal production output from 4 to 11 Mt annually was adopted. It is also required to abide with the industrial safety standards, the major of which is occupational safety and health.

Keywords: endogenous fires, spontaneous combustion, chemical process, chemical reactions, geological features of coal, chemical activity of coal, absorption rate constant, metamorphism, air inflow, heat exchange, solar radiation, water injection, effective porosity ratio, pressure gradient, preliminary coal humidification.

For citation:

Akbarov T. G., Israilov M. A., Makhmudov D. R. Analysis and prevention of spontaneous combustion of Angren coal. MIAB. Mining Inf. Anal. Bull. 2021;(1):170-177. [In Russ]. DOI: 10.25018/0236-1493-2021-1-0-170-177.

Acknowledgements:

About authors:

T.G. Akbarov¹, Cand. Sci. (Eng.), Professor, e-mail: taxirjan.akbarov@tdtu.uz,
M.A. Israilov¹, Senior Lecturer, e-mail: mansur.israilov.78@mail.ru,
D.R. Makhmudov¹, PhD., Head of Chair, e-mail:mahmudov@mail.ru,
¹ Islam Karimov Tashkent State Technical University, Tashkent, 100095, Republic of Uzbekistan.

 

For contacts:

D.R. Makhmudov, e-mail: dmahmudov@mail.ru.

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